The present invention generally relates to toilets and, more particularly, to vacuum toilet systems.
Vacuum toilet systems are generally known in the art for use in both vehicle and stationary applications. A vacuum toilet system typically comprises a bowl for receiving waste having an outlet connected to a vacuum sewer line. A discharge valve is disposed between the bowl outlet and vacuum sewer line to selectively establish fluid communication therebetween. The vacuum sewer line is connected to a collection tank that is placed under partial vacuum pressure by a vacuum source, such as a vacuum pump. When the discharge valve is opened, material in the bowl is transported to the sewer pipe as a result of the pressure difference between the interior of the bowl and the interior of the sewer line. Conventional vacuum toilet systems also include a source of rinse fluid and a rinse fluid valve for controlling introduction of rinse fluid into the bowl.
Repair and maintenance of vacuum toilet systems is often overly time consuming and labor intensive. Maintenance concerns are particularly significant in aircraft applications, in which a number of sub-systems are installed on board. According to general practice in the airline industry, each sub-system includes one or more components which must be replaced in the event of failure, such components being commonly referred to as line replaceable units (LRUs). Presently, the entire toilet assembly is defined as the LRU for the vacuum toilet system. As a result, an airline must stock one or more replacement toilets in case of a toilet failure, so that the replacement toilet may be swapped in for the faulty toilet. A xe2x80x9cbench testxe2x80x9d is then performed on the faulty toilet to determine which components have failed in the toilet. The faulty components are then repaired or replaced (which may include significant disassembly and reassembly of the toilet) so that the toilet may be reused on another aircraft.
Each of the steps performed during a toilet repair is overly difficult and time consuming. To remove an entire toilet assembly from an aircraft requires disassembly of at least four self-locking mounting fasteners, an electrical connection, a grounding strap, a potable water line connection, and a waste discharge pipe connection. Each connection may be difficult to access, and may require a particular tool in order to loosen and disconnect. The same connections must then be reconnected for the replacement toilet.
Even if it were possible to remove and replace a single toilet component, it would be overly difficult and time consuming to do so. Removal of a component would require disconnection of several wires and pipes, and the components are often located in areas which are difficult to access. Furthermore, it would be difficult to diagnose whether one component or several components had failed. There exists a multitude of combinations of simultaneous component failures, which may lead to trouble-shooting errors and the replacement or repair of non-faulty components.
Certain repairs, which may not require substantial amounts of trouble shooting to identify the failed components, still require significant amounts of disassembly and reassembly. The toilet bowl, for example, is typically formed of stainless steel covered with a non-stick coating that is subject to failure. In conventional toilets, the bowl is a structural, load bearing component that is attached to a base support. In some toilets, the base support is permanently attached to the bowl and therefore the entire toilet must be removed to replace the coating. In other toilets, the bowl is removable from the support base, and therefore fasteners must be removed and the bowl must be disconnected from the rinse fluid and discharge lines. In addition, the rinse ring or nozzle used to direct rinse fluid into the bowl must be removed. Furthermore, if the non-stick coating fails, the bowl must be removed from all of the other toilet components for a re-coating process, steps of which are performed at high temperatures to remove the old coating and apply a new coating to the toilet bowl surface. Accordingly, replacement of a conventional bowl is overly complicated and time consuming.
In addition, the use of the bowl as a structural, load-bearing member in conventional toilets overly limits the selection of bowl materials. Because the bowl must be capable of supporting the weight of a user and any components mounted there to, it is typically made of a metal such as stainless steel. Because only rigid materials may be used, the selection of materials for use in conventional toilet bowls is overly limited.
In accordance with certain aspects of the present invention, a waste receptacle is provided for use in a vacuum toilet system having a discharge valve with an inlet. The waste receptacle comprises a support structure, and a bowl releasably attached to the support structure, the bowl defining an outlet adapted to engage and seal with the discharge valve outlet.
In accordance with additional aspects of the present invention, a vacuum bowl assembly is provided for use in a vacuum toilet positioned on a support surface and having a discharge valve with an inlet. The assembly comprises a frame having a bottom member adapted to engage the support surface, and a top member defining an opening, a pair of slots being formed in the top member. A removable bowl has a sidewall sized for insertion into the opening and a flange carrying a pair of tabs sized to lockingly engage the slots, the bowl defining an outlet adapted for fluid communication with the discharge valve inlet.
In accordance with further aspects of the present invention, a vacuum bowl assembly is provided for use in a vacuum toilet positioned on a support surface and having a discharge valve with an inlet. The assembly comprises a frame having a bottom member adapted to engage the support surface, and a top member defining an opening, a pair of slots being formed in the top member. A removable plastic bowl has a sidewall sized for insertion into the opening and a flange carrying a pair of tabs sized to lockingly engage the slots, the bowl defining an outlet adapted for fluid communication with the discharge valve inlet.
Other features and advantages are inherent in the apparatus claimed and disclosed or will become apparent to those skilled in the art from the following detailed description and its accompanying drawings.